special deployement needed for this:
------------------------------------
stop workers (cleanup nodes) and build_service
prepare jenkins shutdown in gui
do run update_jdn.sh
rename dirs in the filesystem as needed, FIXME: proper mv commands…
	root@jenkins:/var/lib/jenkins/userContent# find . -type d -name "*testing*"
	./reproducible/debian/issues/testing
	./reproducible/debian/logs/testing
	./reproducible/debian/rb-pkg/testing
	./reproducible/debian/logdiffs/testing
	./reproducible/debian/buildinfo/testing
	./reproducible/debian/dbdtxt/testing
	./reproducible/debian/rbuild/testing
	./reproducible/debian/dbd/testing
	./reproducible/debian/testing
	./reproducible/rpms/fedora-23/x86_64/gnome-desktop-testing
	root@jenkins:/var/lib/jenkins/userContent#
	root@jenkins:/srv/reproducible-results# find . -type d -name "*testing*"
	./meta_pkgsets-testing
	./chdist-testing
	./chdist-testing/testing-amd64
	root@jenkins:/srv/reproducible-results# 
run reproducible_db_maintenance
reenable job execution
do run update_jdn.sh again
remove all jobs which match reproducible*testing*

changes not to be done
----------------------
hosts/jenkins/etc/apache2/sites-available/jenkins.debian.net.conf has no (new) redirects from testing to stretch, I think that's good enough

changes not yet prepared in git
-------------------------------
db changes
prepare to add buster on 2017-06-17
finally, remove this file again.